If your iPhone experience is anything like mine, Face ID doesn't always work. And even if it does work for you most of the time, you probably still find yourself typing in your passcode occasionally when unlocking your phone while wearing sunglasses, or when you simply don't feel like lifting it up to get an accurate view of your face.
Other phone makers like Samsung, OnePlus, and Google also include fingerprint scanners on their devices as an alternative — some of which are embedded in the display, and others which are located on the back of the device.